Hi. I have some bathroom fan temporizers built with CD4001 and I wonder if I can introduce a delay in fan starting (temporizer power up) in order not to start if the light is open for less than 3 minutes for instance. Actual function is the fan starts after 5 seconds of light stay open and the temporizer shut off the fan in 15 minutes (adjustable by a potentiometer) after the light is turned off. Those 5 second I want to adjust. Thank You!

The CD4001 is a CMOS quad NOR gate. While I can think of several ways to use it for this function without a schematic we'll be spitting in the wind. A picture might help, but the schematic is the thing.